V-belt routing

[mrk5]

I'm trying to figure out if my belt routing is correct on the 1973 350 with A/C. Does anyone know of a source for belt drawings.

This is how mine is setup.



What confuses me is the parts places list the crank-p/s belt as being for w/o A/C application.

The alternative is Fan & P/S with A/C.

Maybe when they say "w/o A/C" they just mean the belt doesn't go over the A/C clutch not that the truck isn't equipped with it.

 

[6872xtc]

I have seen some that didn't go over the water pump and went to the crankshaft just under the water pump pulley. But if what you have is working, what are you questioning? I believe that you diagram should work.

 

[Big Ray]

All the Chevy 350's I've had with v belts have had a dedicated p/s belt and a shared belt like your drawing. So does my 6.2l BTW...

 

[frankin5]

It is the way my 85 was.

 

[ktmoutfront]

I went through bgg this once. You are correct that the without ac is because it does not feed to the compressor. The ac pulley should be a single groove.

 

[mrk5]

I have seen some that didn't go over the water pump and went to the crankshaft just under the water pump pulley. But if what you have is working, what are you questioning? I believe that you diagram should work.

Because the A/C compressor belt is kind of a pain. It's like a puzzle between the A/C and the P/S. I was hoping there was a better way.

Turns out my diagram is wrong tho. I only have 1 groove on the water pump pulley. So both the A/C and P/S do NOT ride on the water pump.

 

[6872xtc]

That's what I am used to seeing.
And yes, it is something of a pain, but how often do you have to mess with it?
In the old days, it wasn't much of a problem, no one had invented the serpentine belt systems, so there wasn't a better option out there!


You could LS swap it!


I figured that someone needed to say that today..

 

[mrk5]

I shouldn't need to mess with it, but lately it seems to be more regular. Hopefully I'm done with it for a while.

 

[blazer74]

Alt/crank/fan 1 groove
Ps/crank/fan 2 groove
Ac/crank/ps 3 groove

 

[mrk5]

Alt/crank/fan 1 groove
Ps/crank/fan 2 groove
Ac/crank/ps 3 groove

View attachment 341105

View attachment 341106

The big difference for mine is the water pump is just 1 groove. I like your setup better with 2 belts on the water pump. If I get motivated, I could probably just pick up a new water pump pulley with 2 grooves and match yours.

 

[blazer74]

The big difference for mine is the water pump is just 1 groove. I like your setup better with 2 belts on the water pump. If I get motivated, I could probably just pick up a new water pump pulley with 2 grooves and match yours.

Would say that single groove fan pulley has been changed at some point.
Mine is the factory set up 1974 K5

 

[mrk5]

Would say that single groove fan pulley has been changed at some point.
Mine is the factory set up 1974 K5

That's what I'm wondering too.

 

[6872xtc]

Would say that single groove fan pulley has been changed at some point.
Mine is the factory set up 1974 K5

I wouldn't bet on it being changed. Like I said, I have seen factory stuff just like what @mrk5 posted. Heck, they could have made the '73 C10 different from a '74 K5 in that pulley.

I wouldn't worry about it if all works well. Why put more pressure on the top side of the water pump bearings if there isn't a problem to fix? If the pulley isn't slipping under the belt and causing the belt to glaze, why worry?

 

[mrk5]

I wouldn't bet on it being changed. Like I said, I have seen factory stuff just like what @mrk5 posted. Heck, they could have made the '73 C10 different from a '74 K5 in that pulley.

I wouldn't worry about it if all works well. Why put more pressure on the top side of the water pump bearings if there isn't a problem to fix? If the pulley isn't slipping under the belt and causing the belt to glaze, why worry?

The nerdy side of me says it would be better because you'd have offsetting tension on the water pump with a belt pulling in each direction instead of just one.

You could be right about the differences between 73 & 74, but typically the 73-74 stuff is unique from the 75 and later stuff. I would be curious if my belt layout is more typical to the 67-72 trucks and I have a little bit of overlap.

 

[6872xtc]

The nerdy side of me says it would be better because you'd have offsetting tension on the water pump with a belt pulling in each direction instead of just one.

You could be right about the differences between 73 & 74, but typically the 73-74 stuff is unique from the 75 and later stuff. I would be curious if my belt layout is more typical to the 67-72 trucks and I have a little bit of overlap.

I understand the angle of putting tension on both sides, but the forces aren't completely opposing. The wrap up on the top will push down some as well. I remember when I lost a bearing in one years ago, and the belt got loose and the alternator quit charging. The fan got close to the shroud.
Sometimes it's fine to leave things alone if there isn't a problem.

And the '67-'72 trucks have a short water pump, so things aren't exactly the same.

 

[mrk5]

I was wondering how long it'll be before car people don't know what a v-belt is or even how to tension them. I was even thinking it could get harder to find them in the parts stores.